1. Field of the Invention
The present invention relates to a high-density mounted module containing an active component such as a semiconductor etc. and a passive component such as a resistor, a capacitor, etc.
2. Description of the Prior Art
Recently, with a demand for high performance and miniaturization of electronic equipment, high density and high performance of a semiconductor have been increasingly desired. This leads to a demand for a small size and high-density circuit substrate on which such a semiconductor is to be mounted. In order to meet such demands, a connection method using an inner via that can connect between wiring patterns of LSIs or components in the shortest distance has been developed in various fields in order to achieve higher density mounting.
However, there is a limitation in mounting components two-dimensionally with high density even with the above-mentioned methods. Furthermore, since these high-density mounted substrates having an inner-via structure are formed of a resin-based material, the thermal conductivity is low. Therefore, as the mounting density of components becomes higher, it is getting more difficult to release heat that has been generated by the components. In the near future, a clock frequency of a CPU is expected to be about 1 GHz. It is estimated that with the sophistication in the function of the CPU, its electric power consumption accordingly will reach 100 W to 150 W per chip. Furthermore, in accordance with high speed and high density, the effect of noise cannot be ignored. Therefore, there is an expectation for a module in which components are contained three-dimensionally, in addition to a circuit substrate with a high-density and high-performance, as well as an anti-noise property and a thermal radiation property.
In order to meet such demands, JP 2(1990)-121392A proposes a module in which a multilayer ceramic substrate is used as a substrate and a capacitor and a register are formed in an internal portion of the substrate. Such a ceramic multilayer substrate is obtained by processing a material that has a high dielectric property and can be fired simultaneously with a substrate material into a sheet and then firing the sheet sandwiched between the substrates. However, in the case where different kinds of materials are fired simultaneously, due to a lag in sintering timing or difference in the shrinkage at the time of sintering, the multilayer substrate may suffer some warping after being fired or an internal wiring may be peeled off. Therefore, it is necessary to control firing conditions precisely. Furthermore, the components involved in a ceramic substrate are based on simultaneous firing as mentioned above. Therefore, it is possible to include a capacitor, a resistor, or the like, but it is impossible to fire a semiconductor of silicon etc., which lacks in thermal resistant property, simultaneously, and thus the semiconductor cannot be contained.
On the other hand, a circuit substrate in which an active component such as a semiconductor etc. and a passive component such as a capacitor, a resistor etc. are contained at low temperatures is proposed. JP 3 (1991)-69191 A and JP11 (1999)-103147 A describe a method including the steps of: mounting electric components onto a copper wiring formed on a printed wiring board material; further coating the entire surface of the printed wiring board with resin so as to form a buried layer; and then adhering a plurality of layers by an adhesive. Furthermore, JP 9 (1997)-214092 A describes a method including the steps of: burying a material such as a dielectric material etc. in a through hole; forming a surface electrode and allowing a capacitor or a resistor to be included. In addition, there also is a method of adding a function of a capacitor etc. into a printed wiring board itself. JP 5 (1995)-7063 A (U.S. Pat. No. 3,019,541) describes a capacitor built-in substrate in which electrodes are formed on both surfaces of the dielectric substrate obtained by mixing dielectric powder and resin. Furthermore, JP11 (1999)-220262 A describes a method for allowing a semiconductor, a capacitor, or the like to be contained in an inner-via structure.
As mentioned above, a conventional three-dimensionally mounted module having an inner via structure capable of realizing a high-density wiring and containing components is classified into two types: a module using a ceramic substrate that is excellent in the thermal radiation property and the air tightness; and a module that can be cured at a low temperature. The ceramic substrate is excellent in the thermal radiation property and capable of containing a capacitor with high dielectric constant, but it is difficult to fire different kinds of materials simultaneously and it is impossible to include a semiconductor. Also, there is a problem from a viewpoint of cost. On the other hand, a printed wiring board that can be cured at low temperatures has a possibility of including a semiconductor and is advantageous from the viewpoint of cost, but it is difficult to obtain a high dielectric constant in the case of a composite material mixing a dielectric material, etc. and resin. This is apparent from an example of the capacitor formed in the through hole or a printed wiring board mixing dielectric powder. In general, the printed wiring board has a low thermal conductivity and inadequate in heat resistance property. Furthermore, the method of sealing a semiconductor or a capacitor, etc. mounted on the printed wiring board with resin to allow a plurality of layers to be contained has a problem in which individual components can be contained but the thickness of the module itself for the individual components to be buried becomes large, and thus it is difficult to reduce the module volume. Furthermore, due to the thermal stress due to the difference of the coefficient of thermal expansion between the contained components and the printed wiring board, steps for providing a buffer layer having a constant coefficient of thermal expansion between the component and the printed wiring board material, adjusting the coefficient of thermal expansion of the printed circuit materials, or the like, are taken. However, the coefficient of thermal expansion of the semiconductor is generally small, and it is extremely difficult to adjust the coefficient of thermal expansion only with a printed wiring board material in the range of operation temperatures.
With the foregoing in mind, it is an object of the present invention to provide a thermal conductive component built-in module in which an inorganic filler can be contained in a thermosetting resin at high density, an active component such as a semiconductor etc. and a passive component such as a chip resistor, a chip capacitor, etc. are buried in the internal portion thereof by a simple method, and a multilayer wiring structure can be formed simply. In the present invention, by selecting an inorganic filler and a thermosetting resin, it is possible to produce a module having a desired performance and to provide a component built-in module that is excellent in a thermal radiation property and a dielectric property.
In order to solve the above-mentioned problems, the component built-in module of the present invention includes a core layer formed of an electric insulating material; an electric insulating layer and a plurality of wiring patterns formed on at least one surface of the core layer. In the component built-in module, the electric insulating material of the core layer is formed of a mixture including at least an inorganic filler and a thermosetting resin; at least one or more of active components and/or passive components are contained in an internal portion of the core layer; the core layer has a plurality of wiring patterns and a plurality of inner vias formed of a conductive resin; and the electric insulating material formed of the mixture including at least an inorganic filler and a thermosetting resin of the core layer has a modulus of elasticity at room temperature in the range from 0.6 GPa to 10 GPa.
According to such a configuration, it is possible to provide a module allowing an active component such as a semiconductor etc. and a passive component such as a chip resistor, a chip capacitor, etc. to be buried with a simple technique, having a desired performance and a high reliability with respect to stress such as a thermal shock, by selecting a suitable inorganic filler and thermosetting resin. Namely, it is possible to adjust the coefficient of thermal expansion of the module in the in-plane direction to that of a semiconductor, or to provide the module with a thermal radiation property. In addition, by setting the modulus of elasticity of the electric insulating material at room temperature to be in the range from 0.6 GPa to 10 GPa, a component such as a semiconductor can be contained without stress. Therefore, it is possible to provide a module having a high-density mounting structure. Furthermore, since it is possible to form a multilayer high density wiring layer capable of re-wiring on the surface of the core layer in which a component is contained, an ultra-thin and high-density module can be realized. Furthermore, the problem of noise that may be caused in accordance with a future development of high frequency can be expected to be reduced by arranging the semiconductor and the chip capacitor extremely close to each other.
Furthermore, the component built-in module of the present invention has a configuration in which the electric insulating material formed of the mixture including at least an inorganic filler and a thermosetting resin of the core layer has a modulus of elasticity at room temperature in the range from 0.6 GPa to 10 GPa, and the thermosetting resin includes a plurality of thermosetting resins having different glass transition temperatures. According to such a configuration, it is possible to obtain a component built-in module that is strong with respect to a thermal stress by a thermal shock of the contained components, even if components with various coefficient of thermal expansion are present.
Furthermore, the component built-in module of the present invention has a configuration in which the electric insulating material formed of the mixture including at least an inorganic filler and a thermosetting resin of the core layer has a modulus of elasticity at room temperature in the range from 0.6 GPa to 10 GPa, and the thermosetting resin includes at least a thermosetting resin having a glass transition temperature in the range from xe2x88x9220xc2x0 C. to 60xc2x0 C. and a thermosetting resin having a glass transition temperature in the range from 70xc2x0 C. to 170xc2x0 C. According to such a configuration, it is possible to obtain a component built-in module that is further strengthened with respect to a thermal stress by a thermal shock of the contained components, even if components with various coefficient of thermal expansion are present.
Furthermore, it is preferable that the component built-in module of the present invention includes a through hole that extends through all of the core layer, the electric insulating layer and the wiring pattern.
Thus, in addition to the above-mentioned effects, since it is possible to use a usual process and equipment for producing a printed wiring board, a component built-in module can be realized extremely simply.
Furthermore, it is preferable that the component built-in module of the present invention includes a core layer formed of an electric insulating material; an electric insulating layer including an electric insulating material formed of a mixture including an inorganic filler and a thermosetting resin, which is formed on at least one surface of the core layer; and a plurality of wiring patterns formed of a copper foil; wherein the core layer has a plurality of wiring patterns formed of a copper foil and a plurality of inner vias formed of a conductive resin, and the wiring patterns are connected electrically to each other by the inner vias.
According to such a configuration, it is possible to provide a module that allows an active component such as a semiconductor etc. and a passive component such as a chip resistor, a chip capacitor, etc. to be buried with a simple technique, having a desired performance and a high reliability with respect to stress such as a thermal shock, by selecting a suitable inorganic filler and thermosetting resin. In other words, it is possible to adjust the coefficient of thermal expansion of the module in the in-plane direction to that of a semiconductor, or to provide the module with a thermal radiation property. Furthermore, since it is possible to form a multilayer high-density wiring layer capable of re-wiring on the surface of the core layer in which a component is contained in an inner via structure, it is possible to realize an ultra-thin and high-density module.
Furthermore, it is preferable that the component built-in module of the present invention includes a core layer formed of an electric insulating material; an electric insulating layer including an insulating material formed of a thermosetting resin, which is formed on at least one surface of the core layer; and a plurality of wiring patterns formed by copper-plating; wherein the core layer has a plurality of wiring patterns formed of a copper foil and a plurality of inner vias formed of a conductive resin, and the wiring patterns formed by the copper-plating are connected electrically to each other by the inner vias.
Thus, in addition to the above-mentioned effects, it is possible to use the existing plating technique as it is, and it is also possible to make the surface wiring layer and insulating layer to be thin. Therefore, a component built-in module with a smaller thickness can be realized.
Furthermore, it is preferable that the component built-in module of the present invention includes a core layer formed of an electric insulating material; an electric insulating layer formed of an organic film having a thermosetting resin on both surfaces, which is formed on at least one surface of the core layer; and a plurality of wiring patterns formed of a copper foil; wherein the core layer ha s a plurality of wiring patterns formed of a copper foil and a plurality of inner vias formed of a conductive resin, and the wiring patterns are connected electrically to each other by the inner vias.
Thus, a high-density and thin surface wiring layer can be formed, and a surface that has excellent surface smoothness can be achieved by the organic film. Similarly, since the excellent thickness precision can be achieved, an impedance control of the surface wiring layer can be carried out with high accuracy, and thus a component built-in module for high frequency can be realized.
Furthermore, it is preferable that the component built-in module of the present invention includes a core layer formed of an electric insulating material; and a ceramic substrate having a plurality of wiring patterns and inner vias adhered onto at least one surface of the core layer; wherein the core layer has a plurality of wiring patterns formed of a copper foil and a plurality of inner vias formed of a conductive resin.
Thus, it is possible to obtain a module that contains components, has an excellent thermal radiation property or air-tightness, and contains a capacitor having a high dielectric constant.
Furthermore, it is preferable that the component built-in module of the present invention includes a core layer formed of an electric insulating material; and a plurality of ceramic substrates having a plurality of wiring patterns and inner vias adhered onto at least one surface of the core layer; wherein the core layer has a plurality of wiring patterns formed of a copper foil and a plurality of inner vias formed of a conductive resin; and the plurality of ceramic substrates include dielectric materials having different dielectric constants.
Thus, it is possible to laminate different kinds of layers, that is, a ceramic capacitor with high dielectric constant and a ceramic substrate with low dielectric constant suitable for a high-speed circuit. In particular, for the high-speed wiring layer, a ceramic layer with a small transfer loss can be used, while for a portion requiring a bypass capacitor, a ceramic layer with high dielectric constant can be used.
Furthermore, in the component built-in module of the present invention, it is desirable that a film-shaped passive component is disposed between the wiring patterns formed on at least one surface of the core layer. Thus, it is possible to realize a three-dimensional module in which components are contained with higher density.
Furthermore, in the component built-in module of the present invention, it is desirable that the film-shaped passive component is at least one selected from the group consisting of a resistor, a capacitor and an inductor formed of a thin film or a mixture including an inorganic filler and a thermosetting resin. It is advantageous because a thin film can provide an excellent performance passive component. Furthermore, a film-shaped component including an inorganic filler and a thermosetting resin can be produced easily and is excellent in reliability.
Furthermore, in the component built-in module of the present invention, it is desirable that the film-shaped passive component is a solid electrolytic capacitor formed of at least an oxide layer of aluminum or tantalum and a conductive macromolecule.
Furthermore, a method for producing a component built-in module of the present invention includes: processing a mixture including at least an inorganic filler and an uncured state thermosetting resin into a sheet; providing the sheet material including an inorganic filler and an uncured state thermosetting resin with a through hole; filling the through hole with a conductive resin; mounting an active component and/or passive component on a copper foil; and superimposing the sheet material in which the through hole is filled with a conductive resin onto the surface of the copper foil on which the components are mounted. This is followed by superimposing a copper foil; burying the active and/or passive component in the sheet material, followed by heating and pressing the sheet material, thereby curing the thermosetting resin and the conductive resin in the sheet material; then processing the copper foil on the outermost layer into a wiring pattern, thereby forming a core layer; and providing a through hole to a sheet including an inorganic filler and an uncured state thermosetting resin or an organic film having adhesive layers on both surfaces. This is followed by superimposing the copper foil, and the sheet or the organic film in which the through hole is filled with a conductive resin onto at least one surface of the core layer, followed by heating and pressing thereof so as to be integrated onto each other; and processing the copper foil into a wiring pattern.
According to such a method, since it is possible to bury an active component such as a semiconductor etc. and a passive component such as a chip resistor, a chip capacitor, etc. in an internal portion and also to mount components onto the outer layer portion, an extremely high-density and small size module can be realized. Furthermore, since a wiring pattern can be formed also on the surface portion of the core layer, a further high-density module can be realized. Furthermore, since a material of the surface portion can be selected, the thermal conductivity, dielectric constant, coefficient of thermal expansion, etc. can be controlled.
Furthermore, in the method for producing the component built-in module of the present invention, it is preferable that a film-shaped component is formed beforehand on the copper foil that is to be superimposed onto the core layer.
Furthermore, the method for producing a component built-in module of the present invention includes: processing a mixture including at least an inorganic filler and an uncured state thermosetting resin into a sheet; providing a through hole to the sheet material including an inorganic filler and an uncured state thermosetting resin; filling the through hole with a conductive resin; forming a wiring pattern on one surface of a release carrier; and mounting an active component and/or passive component on the wiring pattern of the release carrier. This is followed by superimposing a sheet material in which the through hole is filled with a conductive resin onto the surface of the release carrier having a wiring pattern on which the component is mounted; burying and integrating the active component and/or passive component into the sheet material, followed by further heating and pressing thereof, thereby curing the thermosetting resin and the conductive resin in the sheet material; then peeling off the release carrier on the outermost portion, thereby forming a core layer; and providing a through hole to a sheet including an inorganic filler and an uncured state thermosetting resin or an organic film having adhesive layers on both surfaces. This is followed by superimposing the release carrier having a wiring pattern, and the sheet or the organic film in which the through hole is filled with the conductive resin onto at least one surface of the core layer, followed by heating and pressing thereof so as to be integrated into each other; and peeling off the release carrier.
According to such a method, since it is possible to bury an active component such as a semiconductor etc. and a passive component such as a chip resistor, a chip capacitor, etc. in an internal portion and also to mount further components onto the outer layer portion, an extremely high-density and small size module can be realized. Furthermore, since a wiring pattern can be formed on the surface portion by a transferring process, a treatment such as etching after the curing process is not necessary, thus making the method simple from an industrial viewpoint.
Furthermore, in the method for producing the component built-in module of the resent invention, it is preferable that a film-shaped component is formed on the wiring pattern formed beforehand on the release carrier on which the wiring pattern is formed to be superimposed onto the core layer.
Furthermore, in the method for producing the component built-in module of the resent invention, it is preferable that the film-shaped component is at least one selected from the group consisting of a resistor, a capacitor and an inductor, which is formed of a thin film or a mixture including an inorganic filler and a thermosetting resin; and the film-shaped component is formed by one method selected from the group consisting of vapor deposition method, MO-CVD method or a thick film printing method.
Furthermore, the method for producing a component built-in module of the present invention includes: processing a mixture including at least an inorganic filler and an uncured state thermosetting resin into a sheet; providing a through hole to the sheet material including an inorganic filler and an uncured state thermosetting resin; filling the through hole with a conductive resin; and mounting an active component and/or passive component on a copper foil. This is followed by superimposing the sheet material in which the through hole is filled with a conductive resin onto the surface of the copper foil on which the components are mounted; furthermore superimposing a copper foil; burying the active and/or passive component in the sheet material, followed by heating and pressing the sheet material, thereby curing the thermosetting resin and the conductive resin in the sheet material; then processing the copper foil on the outermost layer into a wiring pattern, thereby forming a core layer; and providing a through hole to a sheet including an inorganic filler and an uncured state thermosetting resin or an organic film having adhesive layers on both surfaces. This is followed by superimposing the copper foil, and the sheet or the organic film in which the through hole is filled with a conductive resin onto at least one surface of the core layer, followed by heating and pressing thereof so as to be cured; and then forming a through hole that extends through the core layer so as to form a through hole by copper-plating.
Thus, since this method can use a conventional through hole technique as it is, based on the core layer containing the components, it is advantageous in industrial viewpoint.
Furthermore, the method for producing a component built-in module of the present invention includes: processing a mixture including at least an inorganic filler and an uncured state thermosetting resin into a sheet; providing a through hole to the sheet material including an inorganic filler and an uncured state thermosetting resin; filling the through hole with a conductive resin; forming a wiring pattern on one surface of a release carrier; and mounting an active component and/or passive component on the wiring pattern of the release carrier. This is followed by superimposing a sheet material in which the through hole is filled with a conductive resin onto the surface of the release carrier having a wiring pattern on which the component is mounted; burying and integrating the active component and/or passive component into the sheet material, followed by further heating and pressing thereof, thereby curing the thermosetting resin and the conductive resin in the sheet material; then peeling off the release carrier on the outermost portion, thereby forming a core layer; and providing a through hole to a sheet including an inorganic filler and an uncured state thermosetting resin or an organic film having adhesive layers on both surfaces. This is followed by superimposing the release carrier having a wiring pattern on one surface, and the sheet or the organic film in which the through hole is filled with a conductive resin onto at least one surface of the core layer, followed by heating and pressing thereof so as to be cured; and then forming a hole that extends through the core layer and carrying out copper-plating thereof to form a through hole.
Thus, since this method can use a conventional through hole technique as it is, based on the core layer containing the components, it is advantageous in industrial viewpoint.
Furthermore, the method for producing a component built-in module of the present invention includes: processing a mixture including at least an inorganic filler and an uncured state thermosetting resin into a sheet; providing a through hole to the sheet material including an inorganic filler and an uncured state thermosetting resin; filling the through hole with a conductive resin; forming a wiring pattern on one surface of the release carrier; and mounting an active component and/or passive component on a wiring pattern of the release carrier. This is followed by superimposing the sheet material in which the through hole is filled with a conductive resin onto the surface of the release carrier having a wiring pattern on which the components are mounted; further superimposing a copper foil and heating and pressing in the temperature range in which the thermosetting resin is not cured; burying and integrating the active components and/or passive components into the sheet material, thereby forming a core layer; peeling off the release carrier from the core layer; and superimposing the ceramic substrate in which at least two or more of inner vias and wiring patterns are laminated onto at least one surface of the core layer from which the release carrier is peeled off, followed by pressing thereof, thereby curing the thermosetting resin in the core layer to be adhered to the ceramic substrate.
According to such a method, similar to the above, an extremely high-density and small size module can be realized. Furthermore, since it is possible to integrate an excellent ceramic substrate with various performances, a further high-performance module can be realized.
Furthermore, in the method for producing the component built-in module of the present invention, it is desirable that a plurality of ceramic substrates having a plurality of wiring patterns and the inner vias are laminated simultaneously via the core layer and the adhesive layer. Thus, various kinds of ceramic substrates can be laminated simultaneously, providing an extremely simple method.